Pathologists utilize various immunohistochemistry (IHC) assays for quantification of cellular material, often in terms of expression values within targeted tissue areas, such as for example the relative number of carcinoma cells versus background stroma and benign epithelial cells within a tissue section. Of course, a myriad of IHC assays are currently available and optimized for expression of various proteins and these methods are not limited to the above example.
IHC assays are optimized for methods of tissue handling that are universally applied to tumor samples in clinics, procedure rooms, radiology suites, operating rooms, and pathology laboratories. Standardized methods include immersion of tissues in buffered formalin followed by processing into paraffin blocks.
From paraffin blocks, the tissue can be sectioned into very thin sections, for example 3-4 μm in thickness, for incorporating into microscope slides. Adjacent tissue sections can then be digitally scanned into a computer system for digital analysis by a pathologist.
In a general sense, one or more IHC stains, or biomarkers, can be applied to a tissue sample and slide for viewing under a microscope. Enabled by the stain, a pathologist may view the slide and mark or count areas tending to indicate the presence of a particular object or material, such as cancer cells. Certain stains, or biomarkers, are well known for use with various target proteins and are generally available and accessible via an internet search to those having skill in the art
Certain whole slide imaging (WSI) and other software methods have become popularized in recent years for the acquisition of diagnostic quality digital images of tissue slides for use in pathology and related fields. Additionally, certain software methods have been developed for image registration and alignment on a digital platform.
In practice, certain single gene assays utilize a single biomarker for application on a tissue section and manual quantification by a trained pathologist, requiring excessive time and subject to human errors in the analysis. Furthermore, it is often problematic for a pathologist to attempt an analysis based on a single biomarker.
Present methods for pathology analysis are limited to physical notation and analysis by a trained practitioner. Currently, there has yet to be developed a method for automation of tissue analysis using one or more biomarkers on a computerized platform.